Electric heater



E. N. LIGHTFOOT.

ELECTRIC HEATER.

APPLICATION FILED APR. 9. 1920.

3 SHEETSSHEET I.

. ENVENTOR 1% 1'7? QflOOZ ATTQRNEY' Patented Jan. 16. 1922.

E. N. LIGHTFOOT.

ELECTRIC HEATER.

APPLICATION FILED APR. 9. 1920.

Patented Jm. 10,1922.

3 SHEETSSHEET 2.

ATTORNEY E. LI G HTFOOT. ELECTRIC HEATER. APPLICATION FILED APR. 9,19:20.

Patented Jan. 10; 1922.

3 $HEETSSHEET 3.

ATTORNEY UNITED srATEs PATENT OFFICE.

nn'wm N. menrroor, or nnwxoax, n. Y.-, nssrenoa To run CUTLER-HAMMERMFG. (70., OF MILWAUKEE,

WISCONSIN, A CORPORATION OI' WISCONSIN.

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Specification 01' Letters Patent.

Application filed April 9, 1920. Serial No. 372,616.

To all wkom'it may concem." v

Be it known that I, EDWIN N. Lren'rroor,

. a citizen of the United States, residing at plate 'with a terminal NewYork, in the county of Bronx and Stateof New York, have invented new anduseful Im rovements in Electric Heaters, of which t e following is aspecification.

This invention relates to electric heater.

More particularly this invention relates to a flat electric heaterhaving a resistor enclosed in but insulated from a sheet metal armor.

An object of this invention is to provide a rugged and durable terminalsupport for such a heater.

Another object is to provide a terminal support which also serves as asupport for a cover box for the terminals.

Another object is to provide a terminal support which will facilitatethe manuface ture of heaters of which it forms a part.

Another object is to provide a projecting support for fiat heaters onwhich all or partof the terminals may be mounted.

- Another object is to provide an enclosed terminal support;

Embodiments of this invention are illustrated in the accompanyingdrawings, in whichi Fig. 1 is a side elevation of a heater provided witha terminal support carrying a terminal insulated fromthe' sup rt.

Fig. 2 is an enlarged longitu inal vertical section through the heaterand its terminal support and terminal.

Fig.5 is a plan of a blank terminal support. a

Fig. 4 is a top plan of a heater in which the base of each terminalsupport form's-a portion of one of the reenforcing plates of the flatheater.

Fig. 5 is a plan of the upper reenforcing support formed integrallytherewith and projecting from each end thereof.

Fig. 6 is a. plan of a blank terminal support arranged to carry twoterminals.

Fig. 7 is a plan of a blank terminal support provided with a perforatedlug for coshown in Fig. 23..

insulating bushing employed to insulate Patented Jan. 10, 1922.

operating with and looking a cover box in position to enclose theterminal.

Fig. 8 is a side elevation of a heater with a cover box enclosing theterminal carried by the terminal support. F1g. 9 is a top plan of theheater shown in-Fig. 8.

Fig. 10 is a top plan of a heater equipped with another form of coverbox. I

Fig. 11 is a view of the terminal support employed in the heater shownin Fi 10.

1g. 12 is a vertical section on t e line 12-12 of Fig. 10. f

Fig. 13 is a plan of terminal support for carrymg two terminals. a

Fig. 14 is a perspective of a heater equipped with the terminal supportof Fig.

3, and a co-operating cover box. Fig.

four terminals.

Fig. '16 a perspective of a heater irquiplpged w1th the terminal supportof mounted upon the terminal supthe resistor has been on Fig. 22 is a'perspective of 'a heater equipped with a terminal support showninFig.21." w m Fig. 23 's a perspective of a heater shown 15 is a planof a terminal support- .for carrying p the one terminaland the cover aportion of the box away to show the a terminal support which maybe'mounted upon the heater after osed in the armor.

in Fig. 21 equipped with a cover box for the terminals.

Fig. 24 is a perspective of the cover box Fig. 25 is a perspective ofatw o piece 1 the electric conductors from the openings support, thesupport may be left extendthrough which they enter the cover box.

Fig. 26 is a verticalsection of the insulating bushing shown in Fig. 25.

Fig. 27 ,s a front elevation of the insulating bushing shown in Fig. 25.

Fig. 28 is a. perspective of another form of cover box.

Fig. 29 is a front elevation of an insulating bushing for use with thecover box shown in Fig. 28.

' insulating bushing shown in Fig. 30 is a verticaLsection through theFig. 29.

Fig. 31 is an elevation of the cover box shown in Fig. 30 equipped with.the insulating bushing shown in Figs. 28 and 29.

The heaters shown in the various figures of the drawings are of flatelectric heaters.

Fig. 2 shows a heater made up of a resistor 37 wound about a core 38 ofinsula tion. The resistor 37 is enclosed in a sheet metal armor madeupof two reenforcmg plates 35 and 40, the former being provided withflan es folded over the latter. The resistor 37 is insulated fromthe'enclosin armor by insulating strips 36 and 37 place on oppositesides of the resistor.

for use with 3 shows the form of terminal 'support the heater shown inFigs. 1 and 2. This terminal support'comprises a base 41 and aperforated extension 42.

If the heater is of the type in which the terminal supports are builtin, that is, the base of each terminal support is clamped in osition bythe flanges of the lower plate, before the flanges of the lower plate 35are Fig.

, folded over the upper plate 40, then a terminal support (Fig. 3). isplaced on top of the insulating strip 39 at each end of the pressureplate 40; The flanges of the lower plate 35 are then folded over theupper plate 40 and the base of each terminal support.

The heaters after being thus formed may be put in a press forcompressing them into very compact structures.

After the heater has been compressed a hollow terminal rivet 43 may bemounted upon each terminal support. The periph-' cry of the perforationin the extension 42 is struck up to provide greater separationbetweenthe terminal support and terminal. An insulating washer 44 placed on oneside of the termlnal support 42 insulates the.

resistor 37 and the one .end of the terminal rivet therefrom. Anotherinsulating washer 45 placed upon the other side of the terminal support42 insulates the other end of the terminal rivet therefrom.- Theinsulating washers 44 and 45 are clamped in position by expanding theends of the ter-\ minal rivet over the washers. the end of the resistor37 being clamped against the washer 44 by and into electrical contact Iwith the adjacent expanded end of the ter-' minal rivet,

.for carrying the terminals.

When the terminal is mounted upon the ing in the same lane with theenclosing armor or may be ent at an angle thereto. Fig. 4 shows oneterminal support havin a long base 50 and another terminal suppor Fig. 6shows a terminal support having a short base 54 and a projectionprovided with two perforations 55 in which terminals may be mounted.This terminal support may be employed in a heater the two terminals ofwhich are to be mounted at the same end thereof.

Fig. 7 shows a terminal support havin a short base 56 provided with aperforate extension 57 and a perforated lug 58. This terminal supportmay be employed where it is desired to enclose the terminals mounted inthe perforated extension 57.

Figs. 8 and 9 show a heater equipped with the terminal support shown inFig. and a cover box 59 enclosing the terminal carried by the support.The cover box is locked in place by a cotter pin 60 extending throughthe perforated lug 58 protrud ing through a slot in the top of the coverbox. An insulated conductor 61 extending through an aperture in the sideof the cover box 59 is connected to the terminal. The conductor isclamped against the terminal by a bolt 48 extending through the hollowcenter of the top of this box and the per-. 'forations 66 permit thepositioning of the cover box inany one of eight different po sitions sothat the conductor to be connected with the terminal of the heater,may'approach from any desired angle and enter the cover box directlythrough the aperture in the side thereof: The terminal support employedwith the circular cover box of Fig. 10 is shown in detail in Fig. 11.The perforated extension of this terminal support is provided with twoshort lugs 71 and a longer perforated lug 70. The perforated lug 70extends through the opening 67 in the top of the cover box and theshorter lugs 71 extend through oppositely positioned perforations 66 inthe top of the cover box. The lugs 71 and the re 'steringrforations 66serve to position t e cover the' cover box to the terminal support. Fig.13- shows a terminal su port having a base 75 and an extension in w 1chare provided two perforations 76 for mounting the terminals side ;byside. Two perforated lugs 77 are formed on the perforated extension ofthe terminal support. Fig. 14 shows a'cover' box 78 employed with aheater equipped with the termlnal support of Fig. 13. Four perforations79 provided in the top of the box and positioned 90 apart permit thecover box to v be. mounted 111 any one of four positions.

, Provided in. the t The electrical conductors extending through theopening 80 in the side of the box may there ore approach from either endor side of the heater. The cover box is locked in place b cotter pins 60extending through theper orated lugs 77.

Figs. 15 and 16 show an E shaped terminal support which may be mountedupon the heater after the other elements thereof have 'been assembledand the heater has been compressed. The base 81 of this terminal supportrests on top of the upper reenforcing plate 40 while the ends 82 overliethe flanges of the lower reenforcing' plate 35.

The ends 82 are rigidly fastened to the flanges of the lower plate bysoldering,-ri'veting,! or spot welding. The extension 83 is perforatedfor mounting four terminals and is provided with two perforated lugs 84for mountin the cover box. 'The extension 83 may be nt at right anglesto the base 81 before being mounted. upon the heater.

Fig. 17 shows the cover '85 which co-operates with the terminal supportshown in Figs. 15 and 16. Openings 87 and 86 are and one side of thecover box so the cori dhctors may enter through either the top or sidethereof.

Figs. 18 and 19 show an L shaped insulating plate which fits in thecover box with the bushings 89 registering-with either the perforations86 .or 87. The insulating strip is held in proper position by theperforated lugs 84 extending throughslots 90or 91.

and the alined slots in the top of thecover ing plate provide additionalinsulation between the entering conductors and the cover box.

The terminal support in Fi 19 carries ane elet'92 insulated from t eextension 83 o the su port by the insulating washers 45. The en s oftheeyelet 92 are expanded over insulating washers 45 to form a seat forarsecond eyelet-94 which clamps the resistor 37 against"the eyelet 92.

Figs. 21'and 22 show a'terminal support having a base 95 the ends ofwhich are struck up slightly for mounting on the flanges of 0x on theheater and cotter pin 60 locksv the lower. reenforcing plate, and anextension 96 carrying oppositel laterally extendmg perforated-ears 97 ana perforated lug 98. The perforations in the ears 97 are to receiveterminal eyelets 92 which are'suit ably insulated from the ears by meansof insulating washers. The upper reenforcing plate 40 extending beyondthe end of the heater is perforated for receiving an insulated eyelet'99 b means of which the heater may be mounted. The resistor. 37 extendsthrough registering apertures in the upper insulating stri and thereenforcing plate 40 to-the terminals.

Fig. 23 shows a terminal cover box locked to theterminal support by a'cotter pin extending through the perforated lug 98. The opening 100 mthe side of the box is provided with a/split insulating bushing 101 formore thoroughly insulating the entering electrical conductor from thecover box. The insulating bushing 101 is shown in detail in Figs. 25, 26and 27, while the -cover box is shown separately in Fig. 24.

Figs. 29 and 30 show a single piece insulating bushing 105 which may beused with the cover box 106 shown in Fig. 28. On each side of theopening 107, through which the electrical conductors enter the box, alug 108 is formed to provide means for locking the insulating bushing105 to the cover box as shown in Fig. 31.

The invention contained .herein is, of course, susceptible of otherembodiments and adaptations.

What is claimed is,

1. In an electric heater having a resistor separated from 'an enclosingarmor by sul'ating strips, the combination-of a terminal supportcomprisin a base mounted upon and a terminal connected to the resistorand carried by but insulated from the extension. 2. An electric heaterhaving in combination a resistor, an enclosing/ armor therefor,insulating'strips separating the resistor and the armor, a terminalsupport having a flat base mounted upon'the armor and provided with anextension, and a terminal connected to the resistorand carried by butinsulated from the extension. box. The bushings carried by theinsulatlating strips, aiterminal support compr sing a flat base mountedu on the armor and prothe armor and provi ed .with an extenslon,

vided with an extension, and a terminal for the resistor clamped to andinsulated from the extension.

.4. An electric heater having in combinationa resistor, an enclosingarmor therefor,-

insulating strips separatingthe resistor and the enclosing armor, aterminal support havin a base mounted upon the armor and provi ed with aperforated extension, an insulating washer on each side of theperforatediextension, and a terminal rivetconnected to the resistor andextending through the perforated extension and washers to clamp the sametogether. v 5. A'heater having in combination a resistor, an armorenclosing the resistor insulating strips separating the resistor rom thearmor, a terminal support supported by the armor, a terminal for theresistor insulated from and carried by the terminal support, a cover forenclosing the terminal, and locking means for locking the cover to theterminal su port.

' 6. An electric lieater comp ising a resistor, an enclosing armortherefor, insulating strips separating. the resistor and the armor, a

terminal support having a base supported by the armor and provided withan extension, a lugformed on the extension, a tering strips separatingthe resistor and theminal for the resistor carried by and'insulated fromthe extension, a cover for the terminal having an aperture through whlchthe;

lugextends, and locking means. engagingthe lug to lock the cover to thesupport.

7. A'heater having in combmation a re-' sistor, an enclosing armortherefor, insulatarmor, a terminal support having a base supported bythe armor and provided with an extension, a lug formed on the extension,a terminal for the resistor carried by and insulated from the extension,and a cover for the terminal having an aperture through a which the lugextends so as to position the cover over the terminal.

.8. A heater comprising a resistor, an enclosing armor therefor,insulating strips separating the resistor and the armor, a terminalsupport having a base supported by the armor and provided with anextension",- positioning lugs and a perforated lug formed on theextens1on, a terminal for'the resistor .carried by and insulated fromthe extension,

a cover for. the terminal having apertures with which the positiomnglugs register andan aperture through which the perforated Y lug extends,and a pin extending through the perforated lug so asto lock the cover.to the support.

9. A heater having in combination aterminal sup ort, a terminalinsulated from-- and carrie by the supp ort, a cover for the terminalheld in position by the terminal support, an electric. conductorconnected with the terminal and extending through an opening provided inthe cover, an insulating bushing for the opening held in position by.the co-operation of .the cover and the terminal support. p 10. A heaterhaving in combination a terminal support, a terminal insulated. from andcarried by the support, a conductorconnected to the terminal, a coverfor the terminal having an opening through which the conductor extends,and means for locking the cover to the terminal support.

11. A heater having in combination a. terminal support, a. terminalinsulated fromsistor, a pair of plates forming an enclosure for theresistor, insulating strips separating the resistor from the plates, anextension for one of the plates, a terminal for the resistor lnsulatedfrom and carried by the extension,

a lug formed on the extension, and a cover for the'terminal having anaperture with which the lug registers to position the cover.

In witness whereof, I have hereunto subscribed my name. 1

EDWIN N. LIGHTFOOT.

